Answer:
F = 120.25 10⁻⁹ N
Explanation:
In this exercise, the force between the closest neighbors is indicated by f = 481 10⁻⁹ N, in general between the one-dimensional solid the distances remain the same, if the distance between the first neighbor is d, the distance between the second neighbors is 2d.
For most solids the attractive forces are electrical, therefore force is proportional to the electrical charges and the inverse of the distance squared,
F = [tex]k \frac{q_1 q_2}{r^2}[/tex]
if we call fo the force for the first neighbors
F₀ = k \frac{q_1 q_2}{d^2}
the force for the second neighbors r= 2d
F = k \frac{q_1 q_2}{(2d)^2}
F = F₀ / 4
let's calculate
F = 481 10⁻⁹ / 4
F = 120.25 10⁻⁹ N
.1 An 8-ft 3 tank contains air at an initial temperature of 808F and initial pressure of 100 lbf/in. 2 The tank develops a small hole, and air leaks from the tank at a constant rate of 0.03 lb/s for 90 s until the pressure of the air remaining in the tank is 30 lbf/in. 2 Employing the ideal gas model, determine the final temperature, in 8F, of the air remaining in the tank
Correct temperature is 80°F
Answer:
T_f = 38.83°F
Explanation:
We are given;
Volume; V = 8 ft³
Initial Pressure; P_i = 100 lbf/in² = 100 × 12² lbf/ft²
Initial temperature; T_i = 80°F = 539.67 °R
Time for outlet flow; t_o = 90 s
Mass flow rate at outlet; m'_o = 0.03 lb/s
Final pressure; P_f = 30 lbf/in² = 30 × 12² lbf/ft²
Now, from ideal gas equation,
Pv = RT
Where v is initial specific volume
R is ideal gas constant = 53.33 ft.lbf/°R
Thus;
v = RT/P
v_i = 53.33 × 539.67/(100 × 12²)
v_i = 2 ft³/lb
Formula for initial mass is;
m_i = V/v_i
m_i = 8/2
m_i = 4 lb
Now change in mass is given as;
Δm = m'_o × t_o
Δm = 0.03 × 90
Δm = 2.7 lb
Now,
m_f = m_i - Δm
Thus; m_f = 4 - 2.7
m_f = 1.3 lb
Similarly in above;
v_f = V/m_f
v_f = 8/1.3
v_f = 6.154 ft³/lb
Again;
Pv = RT
Thus;
T_f = P_f•v_f/R
T_f = (30 × 12² × 6.154)/53.33
T_f = 498.5°R
Converting to °F gives;
T_f = 38.83°F
The final temperature, in °F, of the air remaining in the tank is 38.83°F
It is given that volume V = 8 ft³
Initial Pressure Pi = 100 lbf/in² = 100 × 12² lbf/ft²
Initial temperature Ti = 80°F = 539.67 °R
Time for outlet flow; to = 90 s
Mass flow rate at outlet; m'o = 0.03 lb/s
Final pressure; Pf = 30 lbf/in² = 30 × 12² lbf/ft²
Now, from ideal gas equation,
Pv = RT
where v is initial volume, R is ideal gas constant = 53.33 ft.lbf/°R
[tex]v = RT/P\\ \\ v_i = 53.33 *539.67/(100*12^2)\\ \\ v_i = 2 ft^3/lb [/tex]
The initial mass is;
[tex]m_i = V/v_i\\ \\ m_i = 8/2\\ \\ m_i = 4 lb [/tex]
Now change in mass is given as;
Δm = [tex]m'_o*t_o[/tex]
Δm = 0.03 × 90
Δm = 2.7 lb
[tex]m_f[/tex] = [tex]m_i[/tex] - Δm
[tex]m_f[/tex] = 4 - 2.7
[tex]m_f[/tex] = 1.3 lb
now,
[tex]v_f = V/m_f\\ \\ v_f = 8/1.3\\ \\ v_f = 6.154 f^3/lb [/tex]
From the gas equation
Pv = RT
Final state:
[tex]T_f = P_fv_f/R\\\\ T_f = (30*12^2*6.154)/53.33\\\\ T_f = 498.5^oR [/tex]
Converting to °F:
[tex]T_f[/tex] = 38.83°F is the final temperature.
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plsss answer this plsss answer this plsss answer this plsss answer this
Answer:
I dont see file
dndndndbnfbfbfbfbfbf
Answer:
ye ek rod h or electric ⚡ field h P point
20 points!!!! A 2,00ON steel rod that is 5 meters long is placed in a corner between the floor and a wall, and balanced at an angle using a cord attached to the wall The rod is balanced such that its top end is 2.38 meters away from the wall, The cord is 40 cm long, and it is attached to the wall at a height of 75 cm above the floor. The diagram to the right shows the situation If the lower end of the rod does not slip from the corner, what is the tension in the cord?
Answer:
WE NEED TO ADD ALL 40+2.38 +75+5
Explanation:
PLSE GIVE SOME POINTS DUDE
What is the frequency of a wave of a light is with a wavelength of 4 x 10-7 m?
Answer:
7.5 × 10^14 Hz
Velocity of light = 3×10^8m/s
Frequency = (3×10^8)/(4 x 10^-7)
= 7.5 × 10^14 Hz
write short note on fulcrum
Answer:
The definition of a fulcrum is a pivot point around which a lever turns, or something that plays a central role in or is in the center of a situation or activity.
A ball is rolling with a constant acceleration of 13 m/s starting from rest. How long will it take to increase its velocity to a final speed of 62 m/s?
Time taken : 4.77 s
Further explanationGiven
a = 13 m/s²
vf = final velocity = 62 m/s
Required
time taken
Solution
An equation of uniformly accelerated motion
[tex]\large {\boxed {\bold {x=xo+vo.t+\frac {1} {2} at ^ 2}}}[/tex]
vf = vo + at
vf² = vo² + 2a (x-xo)
x = distance on t
vo / vi = initial speed
vt / vf = speed on t / final speed
a = acceleration
Input the value :
vo =0 ⇒from rest
vf=at
62 m/s = 13 m/s².t
t = 62 : 13
t = 4.77 s
Two loudspeakers are about 10 mm apart in the front of a large classroom. If either speaker plays a pure tone at a single frequency of 400 HzHz, the loudness seems pretty even as you wander around the room, and gradually decreases in volume as you move farther from the speaker. If both speakers then play the same tone together, what do you hear as you wander around the room
Answer:
I hear points of low volume sound and points of high volume of sound.
Explanation:
This is because, since the two sources of sound have the same frequency and are separated by a distance, d = 10 mm, there would be successive points of constructive and destructive interference.
Since their frequencies are similar, we should have beats of high and low frequency.
So, at points of low frequency, the amplitude of the wave is smallest and there is destructive interference. The frequency at this point is the difference between the frequencies from both speakers. Since the frequency from both speakers is 400 Hz, we have, f - f' = 400 Hz - 400 Hz = 0 Hz. So, the volume of the sound is low(zero) at these points.
Also, at points of high frequency, the amplitude of the wave is highest and there is constructive interference. The frequency at this point is the sum between the frequencies from both speakers. Since the frequency from both speakers is 400 Hz, we have, (f + f') = 400 Hz + 400 Hz = 800 Hz. So, the volume of the sound is high at these points.
So, as you wander around the room, I should hear points of high and low sound across the room.
Problem 6: A bullet in a gun is accelerated from rest from the firing chamber to the end of the barrel at an average rate of 6.3 × 105 m/s2 for 8.2 × 10-4 s.Ball,removedc795646bb4371e1754411a7dadf94458c503446af1b6450bb3269c1f97e8ef53removedremoved58b1e9a401041b69266daacea519e828d050d14013adc67f8c64697e40f2ef89removedtheexpertta - tracking id: 0W86-2A-6A-4E-962A-28979. In accordance with Expert TA's Terms of Service. copying this information to any solutions sharing website is strictly forbidden. Doing so may result in termination of your Expert TA Account.show answer No Attempt What is the gun’s muzzle velocity (that is, the bullet’s final speed), in meters per second
Answer:
v = 5.166 10² m / s
Explanation:
We can solve this exercise using the kinematics equations
v = v₀ + at
as the bullet starts from rest its initial velocity is zero
v = a t
let's calculate
v = 6.3 10⁵ 8.2 10⁻⁴
v = 5.166 10² m / s
Three people pull simultaneously on a stubborn donkey. Jack pulls eastward with a force of 80.5 N, Jill pulls with 81.7 N in the northeast direction, and Jane pulls to the southeast with 131 N. (Since the donkey is involved with such uncoordinated people, who can blame it for being stubborn
Answer:
F = 233.52 N, θ' = 351.41º
Explanation:
In this exercise we must find the net force applied on the donkey.
For this we use Newton's second law, where we create a reference frame with the horizontal x axis
let's decompose the forces
Jack
= 80.5 N
Jill
cos 45 = F_{2x} / F₂2
sin 45 = F_{2y} / F₂2
F_{2x} = F₂ cos 45
F_{2y} = F₂ sin 45
F_{2x} = 81.7 cos 45 = 57.77 N
F_{2y} = 81.7 sin 45 = 57.77 N
Jane
cos (270 + 45) = F_{3x} / F₃3
sin 315 = F_{3y} / F₃
F_{3x} = 131 cos 315 = 92.63 N
F_{3y} = 131 sin 315 = -92.63 N
the force can be found in each axis
X axis
F_{x} = F_{1x} + F_{2x} + F_{3x}
F_{x} = 80.5 +57.77 + 92.63
F_{x} = 230.9 N
Axis y
F_{y} = F_{1y} + F_{2y} + F_{3y}
F_{y} = 0 + 57.77 -92.63
F_{y} = -34.86 N
we can give the result in two ways
a) F = (230.9 i ^ - 34.86 j ^) N
b) in the form of module and angle
we use the Pythagorean theorem
F = √(Fₓ² + F_{y}²
F = √(230.9² + 34.86²)
F = 233.52 N
let's use trigonometry for the angle
tan θ = [tex]\frac{F_y}{F_x} }[/tex]
θ = tan⁻¹ (\frac{F_y}{F_x} })
θ = tan⁻¹ (-34.86 / 230.9)
θ = -8.59º
if we measure this angle from the positive side of the x-axis counterclockwise
θ' = 360 -θ
θ‘= 360- 8.59
θ' = 351.41º
A 3" diameter germanium wafer that is 0.020" thick at 300K has 1.015 x 10^17 As atoms added to it. What is the resistivity of the wafer? Germanium has 4.42 x10^22 atoms/cc, electron and hole mobilities are 3900 and 1900 cm^2/(V*s). What is the resistivity of the Ge in ohm*microns?
Answer:
0.546 ohm / μm
Explanation:
Given that :
N = 1.015 * 10^17
Electron mobility, u = 3900
Hole mobility, h = 1900
Ng = 4.42 x10^22
q = 1.6*10^-19
Resistivity = 1/qNu
Resistivsity (R) = 1/(1.6*10^-19 * 1.015 * 10^17 * 3900)
= 0.01578880889 ohm /cm
Resistivity of germanium :
R = 1 / 2q * sqrt(Ng) * sqrt(u*h)
R = 1 / 2 * 1.6*10^-19 * sqrt(4.42 x10^22) * sqrt(3900*1900)
R = 1 /0.0001831
R = 5461.4964 ohm /cm
5461.4964 / 10000
0.546 ohm / μm
Sarah took 204 seconds to bicycle to their grandmother's house, a total of
430 meters. What was their velocity in m/s?
Answer:
2.1m/s towards your grandmother's house
Explanation:
Given parameters:
Time taken = 204s
Distance = 430m
Unknown:
Velocity = ?
Solution:
The velocity is determined by:
Velocity = [tex]\frac{displacement}{time}[/tex]
Velocity = [tex]\frac{430}{204}[/tex] = 2.1m/s towards your grandmother's house
The moon accelerates because it is
A. in a vacuum in space.
B. continuously changing direction.
C. a very large sphere.
D. constantly changing its shape.
Answer:
the Answer is b
Explanation:
because the moon usually orbits around our solar system
As the moon continuously changing direction, it accelerates.
Option B. is correct.
Define acceleration.The rate at which an object's velocity changes with respect to time is called acceleration. Accelerations are measured in terms of vectors. The orientation of the net force acting on an object determines the orientation of its acceleration.
The Moon is kept in orbit around us by the gravity of the Earth. It constantly shifting the Moon's velocity direction. This means that, despite its constant speed, gravity causes the Moon to accelerate all the time.
So, as the moon continuously changing direction, it accelerates.
Option B. is correct.
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A cylindrical resistor element on a circuit board dissipates 1.2 W of power. The resistor is 2 cm long, and has a diameter of 0.4 cm. Assuming heat to be transferred uniformly from all surfaces, determine (a) the amount of heat this resistor dissipates during a 24-hour period, (b) the heat flux, and (c) the fraction of heat dissipated from the top and bottom surfaces.
Answer:
(a) The resistor disspates 103680 joules during a 24-hour period.
(b) The heat flux of the resistor is approximately 4340.589 watts per square meter.
(c) The fraction of heat dissipated from the top and bottom surfaces is 0.045.
Explanation:
(a) The amount of heat dissipated ([tex]Q[/tex]), measured in joules, by the cylindrical resistor is the power multiplied by operation time ([tex]\Delta t[/tex]), measured in hours. That is:
[tex]Q = \dot Q \cdot \Delta t[/tex] (1)
If we know that [tex]\dot Q = 1.2\,W[/tex] and [tex]\Delta t = 86400\,s[/tex], then the amount of heat dissipated by the resistor is:
[tex]Q = (1.2\,W)\cdot (86400\,s)[/tex]
[tex]Q = 103680\,J[/tex]
The resistor disspates 103680 joules during a 24-hour period.
(b) The heat flux ([tex]Q'[/tex]), measured in watts per square meter, is the heat transfer rate divided by the area of the cylinder ([tex]A[/tex]), measured in square meters:
[tex]Q' = \frac{\dot Q}{A}[/tex] (2)
[tex]Q' = \frac{\dot Q}{\frac{\pi}{2}\cdot D^{2}+\pi\cdot D \cdot h }[/tex] (3)
Where:
[tex]D[/tex] - Diameter, measured in meters.
[tex]h[/tex] - Length, measured in meters.
If we know that [tex]\dot Q = 1.2\,W[/tex], [tex]D = 4\times 10^{-3}\,m[/tex] and [tex]h = 2\times 10^{-2}\,m[/tex], the heat flux of the resistor is:
[tex]Q' = \frac{1.2\,W}{\frac{\pi}{2}\cdot (4\times 10^{-3}\,m)^{2}+\pi\cdot (4\times 10^{-3}\,m)\cdot (2\times 10^{-2}\,m) }[/tex]
[tex]Q' \approx 4340.589\,\frac{W}{m^{2}}[/tex]
The heat flux of the resistor is approximately 4340.589 watts per square meter.
(c) Since heat is uniformly transfered, then the fraction of heat dissipated from the top and bottom surfaces ([tex]r[/tex]), no unit, is the ratio of the top and bottom surfaces to total surface:
[tex]r = \frac{\frac{\pi}{2}\cdot D^{2}}{A}[/tex] (3)
If we know that [tex]A \approx 2.765\times 10^{-4}\,m^{2}[/tex] and [tex]D = 4\times 10^{-3}\,m[/tex], then the fraction is:
[tex]r = \frac{\frac{\pi}{2}\cdot (4\times 10^{-3}\,m)^{2} }{2.765\times 10^{-4}\,m^{2}}[/tex]
[tex]r = 0.045[/tex]
The fraction of heat dissipated from the top and bottom surfaces is 0.045.
how do positive and negative acceleration differ?
1. positive acceleration represents an object speeding up; negative acceleration represents an object slowing down
2. positive acceleration moves North or east; negative acceleration moves south or west
3. positive acceleration occurs when there is more velocity than speed; negative acceleration occurs when there is less velocity than speed.
4. positive acceleration occurs when an object changes its speed but not its direction; negative acceleration occurs when an object changes both its speed and direction
Answer:
1. positive acceleration represents an object speeding up; negative acceleration represents an object slowing down
Explanation:
Acceleration is clearly defined as the rate of change of velocity with time. When are body is speeding up as we say, it is accelerating. When a body is coming to rest, it is decelerating.
Positive acceleration occurs when the speed of a moving continues to increase.
Negative acceleration is when the speed of a moving body reduces drastically.
On a scale of 1-10 how much do you care of what people think of you?
Answer:
3
Explanation:
my family i hope thinks of me. And I don't have friends for them to think of me.
What quantity measures the amount of space an object occupies?
A. Volume B.Temperature C. Mass D. Density
Answer:
mas
Explanation:
mass is the amount of space something occupies.
A star can give off white light. Why is this evidence that a star is a blackbody
radiator?
A. White light is made up of many different wavelengths of light.
B. The star reflects the white light.
C. The star absorbs the white light.
D. White light is only one wavelength of light.
O
Answer:
It's A. White light is made up of many different wavelengths of light.
What term is used to describe DNA Replication?
Conservative
Un-conservative
Non-conservative
Semi-conservative
Answer:
Semi-conservative
Explanation:
Each strand of the original DNA molecule serves as a template for the production of its counterpart
True Or False weather conditions in the atmosphere can be recognized through direct observation.
Answer:
yes, we can tell if there will be rain by the swelling in rain clouds, we can also see if a tornado is forming based on the look of the wall cloud. we can use satellites to predict the amount of precipitation or wind.
Explanation:
thank you for ur generosity
Describe the political actions that led to successful conservation in both stories.
Answer:
The political actions that led to successful conservation in both stories were what they call an FC company that makes the forest industry true. They make it out of a factory and it can make it very successful and accomplished.
Explanation:
What is the mass of a block concrete that gains 52,800 joules of energy when its temperature is increased by 5 degrees Celsius specific heat of concrete 880 J/K degrees Celsius
Answer:
12 kg
Explanation:
q = 52,800 J
c = 880 J/(kg * K) Pretty sure you missed the kg here
ΔT = 5 °C = 5 K (reminder that this only applies to ΔT and not T)
q = mcΔT ⇒ m = q/(cΔT) = 52,800 J / (880 J/(kg * K) * 5 K) = 12 kg
The mass of a block concrete that gains 52,800 joules of energy when its temperature is increased by 5 degrees Celsius specific heat of concrete 880 J/K degrees Celsius is 12kg
The formula for calculating the quantity of heat energy absorbed by the block is expressed as:
Q = mcΔt
Q is the quantity of heat = 52,800 Joules
m is the mass of the concrete
c is the specific heat of concrete = 880 J/K
Δt is the change in temperature = 5 degrees
substitute the given values into the formula:
[tex]52800=m(880)(5)\\52800 = 4400m\\m=\frac{52800}{4400}\\m= 12kg[/tex]
Hence the mass of a block of concrete that gains 52,800 joules of energy when its temperature is increased by 5 degrees Celsius specific heat of concrete 880 J/K degrees Celsius is 12kg
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Desperado, a roller coaster built in Nevada, has a mass of 800 kg. It also has a vertical drop of 225 feet down the first hill. The roller coaster is designed so that the speed of the cars at the end of this drop is 80 mi/h. Assume the cars are at rest at the start of the drop. How much work is done by friction on the car as it drops down the hill
Answer:
the work done by friction on the car is 524,582 J.
Explanation:
Given;
mass of the roller coaster, m = 800 kg
distance moved by the coaster, d = 225 ft = 68.58 m
final velocity of the coaster, v = 80 mi/h = 35.76 m/s
The time taken for the coaster to drop down the hill is calculated as;
[tex]t = \sqrt{\frac{2h}{g} } \\\\t = \sqrt{\frac{2\ \times \ 68.58}{9.8} } \\\\t = 3.74 \ s[/tex]
The work done by friction on the car is calculated as;
[tex]W =F\ \times \ d = \frac{mv}{t} \times \ d\\\\W = \frac{800 \ \times \ 35.76 }{3.74} \times \ 68.58\\\\W = 524,582 \ J[/tex]
Therefore, the work done by friction on the car is 524,582 J.
A hiker walks 7.7 miles to the east in 3.6 hours, then turns around and walks 2.1 miles to the west in 2.4 hours. What was the magnitude of her average velocity during the trip?
Answer:
2.18 miles per hour
Explanation:
Given:
A hiker walks 7.7 miles to the east in 3.6 hours.
A hiker walks 2.1 miles to the west in 2.4 hours
To find: magnitude of average velocity during the trip
Solution:
Total distance = 7.7 + 2.1 = 9.8 miles
Total Time = 2.1 + 2.4 = 4.5 hours
Average velocity = Total distance ÷ Total Time =[tex]\frac{9.8}{4.5}=2.18[/tex] miles per hour
Before working this problem, review Conceptual Example 14. A pellet gun is fired straight downward from the edge of a cliff that is 14.7 m above the ground. The pellet strikes the ground with a speed of 27.2 m/s. How far above the cliff edge would the pellet have gone had the gun been fired straight upward
Answer:
23.04 m
Explanation:
We'll begin by calculating the initial velocity of the pellet. This can be obtained as follow:
Height (h) of cliff = 14.7 m
Final velocity (v) = 27.2 m/s
Acceleration due to gravity (g) = 9.8 m/s²
Initial velocity (u) =?
v² = u² + 2gh
27.2² = u² + (2 × 9.8 × 14.7)
739.84 = u² + 288.12
Collect like terms
u² = 739.84 – 288.12
u² = 451.72
Take the square root of both side
u = √451.72
u = 21.25 m/s
Thus, the initial velocity of the pellet is 21.25 m/s.
Finally, we shall determine the maximum height to which the pellet would have gone assuming the gun was fired straight upward. This can be obtained as follow:
Initial velocity (u) = 21.25 m/s
Acceleration due to gravity (g) = 9.8 m/s²
Final velocity (v) = 0 m/s (at maximum height)
Maximum height (h) =?
v² = u² – 2gh (since the pellet is going against gravity.
0² = 21.25² – (2 × 9.8 × h)
0 = 451.5625 – 19.6h
Collect like terms
0 – 451.5625 = –19.6h
–451.5625 = –19.6h
Divide both side by –19.6
h = –451.5625 / –19.6
h = 23.04 m
Therefore, the pellet will reach a maximum height of 23.04 m above the cliff.
kinetic energy portfolio in part 2 the independent changes to----?
4. Sally applies a horizontal force of 462 N with a rope to drag a wooden crate across a floor with a constant speed. The rope tied to the crate is pulled at an angle of 56.00 . c.What work is done by the floor through force of friction between the floor and the crate
Answer:
-6,329.5Joules
Explanation:
Complete question:
Sally applies a horizontal force of 462N with a rope to drag a wooden crate across a floor with a constant speed the rope tied to the crate is pulled at an angle of 56.0degree and sally moves the crate 24.5m. What work is done by the floor through the force of friction between the floor and crate.
Work done = Fd cos theta
F is the horizontal force
d is the distance covered
theta angle of inclination
Substituting into the formula
Workdone = 462(24.5)cos 56
Workdone = 11,319(0.5592)
Workdone = 6,329.5Joules
Hence the workdone by sally is 6,329.5Joules
The work done by friction will be opposite the work done by sally, hence work done by the floor through force of friction between the floor and the crate is -6,329.5Joules
Please Help! Will mark brainliest.
Answer:W = m*g*h
19*9.8*32.4 = 6,032.9 rounded
honestly, I do not know if this is correct so please don't come back at me
hopefully this helps
Explanation: [do the following, if you think I am wrong]
just pick a formula,
plug in the number to the mass, gravity, and height
than multiply
get your answer, but don't forget to round to the nearest tenth
16. An object has a gravitational potential energy 41,772.5 Jof and has a mass of 1550 kg. How high is it
above the ground?
Plz help
Answer:
2.75 m.
Explanation:
From the question given above, the following data were obtained:
Potential energy (PE) = 41772.5 J
Mass (m) of object = 1550 kg
Height (h) =?
Potential energy is the energy possess by an object due to its location. Mathematically, potential energy is expressed as shown below:
PE = mgh
Where
PE => potential energy
m => mass of the object
g => acceleration due to gravity
h => height to which the object is located.
With the above formula, we can obtain the height to which the object is located as follow:
Potential energy (PE) = 41772.5 J
Mass (m) of object = 1550 kg
Acceleration due to gravity (g) = 9.8 m/s²
Height (h) =?
PE = mgh
41772.5 = 1550 × 9.8 × h
41772.5 = 15190 × h
Divide both side by 15190
h = 41772.5 / 15190
h = 2.75 m
Thus, the object is located at 2.75 m above the ground.
You are working as a letter sorter in a U.S. Post Office. Postal regulations require that employees' footwear must have a minimum coefficient of static friction of 0.5 on a specified tile surface. You are wearing athletic shoes for which you do not know the coefficient of static friction. In order to determine the coefficient, you imagine that there is an emergency and start running across the room. You have a coworker time you, and find that you can begin at rest and move 4.38 m in 1.21 s. If you try to move faster than this, your feet slip. Assuming your acceleration is constant, does your footwear qualify for the postal regulation?
Answer:
μ = 0.66, therefore if it compiesy with the regulations
Explanation:
Let's solve this exercise in part, let's start by finding with kinematics the acceleration of man
y = v₀ t + ½ a t²
as it starts from rest the initial velocity is zero
y = ½ a t²
a = [tex]\frac{2y}{t^2}[/tex]
a =\frac{2 \ 4.38}{1.21^2}
a = 6.46 m / s²
Now let's use Newton's second law,
Axis y
N- W = 0
N = W
N = m g
X axis
on this axis the man exerts a backward force and by the law of action and reaction the floor exerts a forward force of the same magnitude, this forward force is the friction force.
fr = m a
the friction force has an expression
fr = my N
let's substitute
μ mg = m a
μ = a / g
let's calculate
μ = 6.46 / 9.8
μ = 0.66
therefore if you comply with the regulations
a sensor light installed on the edge of a home can detect motion for a distance of 50 feet in front and with a range of motion of 200 degrees. what is the arc length of the area covered
Answer:
4363.3231 feets²
Explanation:
Given that :
Distance, r = 50 ft
θ = 200°
The arc length of area covered :
Arc length = θ/360° * πr²
Arc length = (200/360) * 50 ft ^2 * π
Arc length = 0.5555555 * 2500 * π
Arc length = 4363.3231 feets²
